Nutrients cause consolidation of soil carbon flux to small proportion of bacterial community

Nature Communications

Bram W. Stone

Junhui Li

Benjamin J. Koch

Steven J. Blazewicz

Paul Dijkstra

Michaela Hayer

Kirsten S. Hofmockel

Xiao-Jun Allen Liu

Rebecca L. Mau

Ember M. Morrissey

Jennifer Pett-Ridge

Egbert Schwartz

Bruce A. Hungate

Carbon cycle

Microbial ecology

2021-06-07

10.1038/s41467-021-23676-x

https://www.nature.com/articles/s41467-021-23676-x

Nutrient amendment diminished bacterial functional diversity, consolidating carbon flow through fewer bacterial taxa. Here, we show strong differences in the bacterial taxa responsible for respiration from four ecosystems, indicating the potential for taxon-specific control over soil carbon cycling. Trends in functional diversity, defined as the richness of bacteria contributing to carbon flux and their equitability of carbon use, paralleled trends in taxonomic diversity although functional diversity was lower overall. Among genera common to all ecosystems, Bradyrhizobium, the Acidobacteria genus RB41, and Streptomyces together composed 45–57% of carbon flow through bacterial productivity and respiration. Bacteria that utilized the most carbon amendment (glucose) were also those that utilized the most native soil carbon, suggesting that the behavior of key soil taxa may influence carbon balance. Mapping carbon flow through different microbial taxa as demonstrated here is crucial in developing taxon-sensitive soil carbon models that may reduce the uncertainty in climate change projections.

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